Drive mechanism



June 6, 1950 H. HERMAQNY 2,510,109

DRIVE MECHANISM Filed Oct. 1, 1945 2 Sheets-Sheet 2 Patented June 6,1950 UNITED STATES PATENT OFFICE na ve MECHANISM Hein ich llermannValley S r m, Y a

s gner o Ben x A ti n o t on, Bro klyn, ,N, 122, acorporation ofDelaware Application October 1, 1945, Serial No. 619,705

7 Cl im 1.

Thepresent invention relates to drive mechanisms, and more particularlyto those employin a frictional roller and disc assembly and utilized toprovide a variable ratio drive between driving and driven parts of anintegrating or like device, although it is not limited to such use.

Although frictional drives of this character have been heretoforeproposed, and some of them have gone into fairly wide use, they do notpro.- vide all of the operating characteristics desired, particularlywhen they are subjected to appree ciable shocks during operation. Manyof them are open to the objection that they embody parts which arethrown out of alignment when subjected. to the shocks and stresses ofnormal opera-.- tion, and all of them are open to the further ob!jeetion that they apply traversing forces to the roller in such mannerthat undue friction is set up, which not only introduces error into thedrive but also subjects the parts to a binding action,

which in some instances is sufliciently severe v to strain or break theparts.

It is accordingly the major object of this invention to provide a novelvariable speed frice tion drive which overcomes all of the disadvanfitages of the devices of the prior art and which is of rugged yet simpleform, is capable of Withstanding considerable shocks without damage, andwhich retains its accuracy throughout its life. a

A further important object is to provide a novel variable speed frictiondrive in which the roller is urged in one traversing direction, againstthe action of resilient means by an actuator, and the resilient meansand the actuator coact with each other and the roller in such mannerthat there is no tendency for the roller to become misaligned when theroller is undergoing traversing moves ment in either direction.

A further object is to provide a friction drive device "having a novelroller shaft assembly which affords the roller adequate support at alltimes, embodies an output shaft which is axially restrained againstmovement, so as to permit power to be delivered without resort to auniversal joint or other structure, pro: viding end play, and yet theroller maybe freely traversed across the face of the disc, so as to varythe speed ratio between its maximum and minimum values.

Another object is to provide a friction disc and roller type of variableratio drive mecha-v nism with a novel movable mount for the disc whichis rockable about an axis parallel to the roller shaft and whichnormally lies substantially in the lane of th d c. so as o m i in the ole n rm to he disc ace at a t mes and all shifted positions of the rollerwith respect to the disc axis.

A u r j t i p ovide. in a variable speed drive of the disc and rollertype, a novel unitary carriage assembly for the roller, which affordsjournalled support for it and at the same time provides for traversingthe roller across fa e of the d c.-

T n n n r her a ms o pro id a f i tion d s an r l r d i e m chan smembeds s novel a ns. e ring and lubr t on ea: tures, an o e mprovem nt afinements w h ll be e einaiter oin d o An r o ject i to pr vid a fri ton dr ve o t d a d oll r ime with a novel radial a d axial 1oad=sustanins bea in assembly and m ans o assuring pro er lubr cation h reof a 1tme Furth r obje s i l. bec m appa en as he sp ific ti n proceeds i conunctio i h the annexed drawin an from he apreud d cl ims In h d awi gs;

Fi 1 is a horiz ntal s c io a w r ugh a drive mechanism embodying theinvention and is taken substantially on the line l-I of Fig, 2.

Fig. 2 is a front elevational view of the mechanism shown in Fig. v1.

Fig. 3 is a sectional view taken substantially on the line '3-3 of Fig.2, looking in the direction of the arrows.

Fig, 4 is an end elevational view of the apparatus of Fig. 2, as itappears when viewed from the right-hand end thereof, and with the gearwheel removed, and

Fig. 5 is a fragmental view illustrating the manner in which the ends ofthe springs are anchored to the standard.

With continued reference to the drawings, wherein like referencecharacters have been employed to designate similar parts throughout theseveral views thereof, the device comprises a base ll! of suitable formand which is secured to a suitable support I! by a plurality of capscrews I2. The support is only illustrated in Fig. 1, so as to simplifythe disclosure.

Referring more particularly to Figs. 1 and. 2, base to is provided witha pair of bosses l3 and It in which a shaft I 5 is mounted for limitedrocking movement. The shaft is carried by a pair-0f ears {6 and I"! of aframe-like support l8, and is locked against endwise movement "by setscrews 19 or the like; As seen more clearly in Fig. 3, frame i8 is urgedin a clockwise direction about its pivot by means of a compressionspring "2| which seats in a recess 22 in support It] and acts against acupped spring retainer 23 carried on the shank of a set screw 24. Thelatter is threaded into frame |8 and it is apparent that by rotating theset screw the stress in the spring may be adjustably varied. This isutilized to establish the proper frictional engagement between the discand roller, in a manner which will be hereinafter pointed out.

Frame I8 is provided with a hub portion 25 in which the shaft portion 26of a disc 21 is journalled for free rotation by means of a ball bearingseating in a groove in shaft 26, and a grease retainer ring 3|.

The inner edge of the inner bearing race bears against a shoulder 32 onthe shaft. The outer bearing race is mounted for snug axial slidingmovement in hub 25. Cooperating in rolling engagement with a smooth face33 formed on the rear face of the disc adjacent its periphery, and witha race member 34 seating in a recess in frame l8, are a plurality ofball bearings 35, which are maintained in proper circumferentiallyspaced relationship by means of a bearing retainer 36. The latter iscentered by engaging the outer surface of shaft 26, and axial movementthereof is limited by a collar 31 and a washer 38, theassembly seatingagainst the inner race of bearing 28, as seen in Fig. 3.

Power may be transmitted to disc 21 in any suitable manner. Forinstance, a constant speed motor driven shaft 39, having a pin 4|seating in a recess 42 in the end of shaft 26, has been found to givegood results in practise.

From the structure so far developed it is apparent that radial bearing28 supports disc 21 for free rotation in frame l8, and that ballbearings 35 .are adapted to resist thrustsapplied to the face of thedisc. Also, the pressure with which spring 2| urges the disc assemblyoutwardly may be variably adjusted by threading screw 24 in or out withrespect to frame structure I8.

Rising from base III are two supports or standards 44- and 45, uponwhich the remaining elements of the structure are mounted. As seen inFigs. 2 .and 3, a pair of guide bars or rails 46 and 41 bridge the twostandards and are locked in standard 44 as for instance, by means of setscrews 48. Mounted for guided sliding movement on guides 46 and 41 arethe arms 49 and of a traversing carriage or traveler member 52. A pairof tension springs 53 and 54 are anchored at their ends to standard 45and the arms of member 52, so as to urge the latter to the right towardsthe zero driving position shown in Figs. 1 and 2.

As seen in Fig. 2, the left-hand ends of the springs pass throughopenings in carriage arms 49 and 5| and are turned over to lock them inplace. The right-hand ends of the springs, as seen in Fig. 2, areprovided with inturned portions which'seat in the bottoms ofopen-ended:lts 69 formed in the ends of guide rails 46 and 'Secured to the arms ofmember 52, by means of screws 55, are the arms 56 and 51 of a secondcarriage member 58, which, as seen in Fig. 1, is provided with anaxially extending, externally threaded sleeve portion 59. Arms 56 and 51are provided with recesses 59 and 60 respectively (Fig. 3), which fitover arms 49 and 5| and accurately locate the two parts of the carriage.

Members 52 and 5B are accordingly rigidly connected together for unitaryguided movement along rails 46 and 41 under the influence of springs 53and 54, and they coact to provide a carrier or carriage having spacebetween them in which a comparatively thin disc-like roller 6| isjournalled. The roller is secured by screws 62 to the flange of a hubmember 63, and the latter is provided with oppositely extending sleeveportions which are journalled in ball bearing assemblies 64 and 65. Thebearings .are carried within members 52 and 58 respectively. The outerrace of bearing 64 is restrained against movement out of member 52 bymeans of split (snap-ring 66 whereas the outer race of bearing 65iskpress fitted-into its seat in member 58.

From the foregoing it is apparent that roller 6! is supported for freerotation in bearings in the carriage assembly, and'the latter, bysliding on rails 46 and 41, makes it'possible to accurately traverse theroller across the face of disc 21, without relying upon the driven shaftfor any substantial degree of support.

It should be particularly observed that guides 46 and 41 are so locatedas to dispose the axis of rotation of roller 6| along a diameter of disc21 (Fig. 2); that frame structure l8 carrying disc 21 is mounted forrocking movement about an axis disposed exactly parallel to the axis ofroller 6|; and that axis of pivot l5 exactly coincides with the plane ofthe driving face of disc 21. By relating the parts in this manner,spring 2| causes disc 21 to establish a driving pressure between it androller 6| which is constant, irrespective of the shifted or traversedposition of the roller with respect to the disc, and that any minorrocking of frame structure l8 about its pivot l5, in response to wear ofthe parts, does not result in disposing roller 6| out of itsperpendicular relationship to the face of the disc.

The roller is traversed with respect to the face of the disc by means ofa sleeve 68, which has an internally threaded portion 69 engaging thethreads of sleeve 59, and it is journalled in a large ball bearing 1|located in a seat in standard 45. The ball bearing is of substantialsize and is of the combination radial and axial load type, so as toafford adequate support for the sleeve. Its outer race is held inassembled relationship to standard 45 by means of a retainer ring 12 andcap screws 13. Its inner race is press-fitted over the sleeve intoengagement with a shoulder 14. Secured on the end of the sleeve, by aset screw 15 or the like, is a gear wheel 16, which may be rotated by amating gear (not shown) to produce the proper rotation of sleeve 68 toeffect the desired roller traverse and resultant speed ratio. Ifdesired, however, any other suitable means may be employed to rotatesleeve 68, it being noted that due to the use of single screw threadedengaging parts it is possible to produce an extremely accuratetraversing movement of the roller, in asmuch as sleeve 68 must undergoseveral com plete revolutions to traverse the roller from the zeroposition of Figs. 1 and 2, into the maximum speed ratio positionadjacent the left-hand periphery of the disc, and any back-lash in theparts is effectively eliminated by springs 53 and 54. Referring to Fig.5, it is observed that retainer plate 12 overlaps the ends of guiderails 46 and 41 and hence restrains them against movement to the rightwith respect to standard 45.

The resulting power is taken ofi or delivered by a shaft II which isviournalled at: its. left=hhnd set screw 84. The screw is threaded into.hub 63- and is locked against removal by the roller. The right hand endof shaft 5:! is journalled in a bearing 85, whose outer race seats in arecess in sleeve 68 and is locked in place therein by means of a splitsnap-ring 85. Shaft H is restrained against axial movement with respectto the inner race of bearing 85 by means of a split snap-ring, 81, whichseats in a groove. 88 in the shaft. This effectively restrains the shaftagainst; endwise movement, since bearing 85 is of the deep race radialand axial load type.

From the foregoing it is apparent that while roller 6|. derive somedegree of; support from shaft 1?, it is supported primarily by bearings64 and 65, which in turn are mounted on the carriage and guided foraccurate axial movement on the guide rails exactly parallel to shaft TI.There is accordingly no tendency for the shaft to undergo misalignmentunder the pressure of the disc and spring 2|. This feature, incombination with the novel traversing mechanism of the invention, whichinsures that the traversing and spring force applied to the carriage areexerted exactly parallel to the axis of the roller, and therebyprecludes the setting up of binding tendencies, provides a frictiondrive which overcomes all of the disadvantages of the devices heretoforeproposed, in a rugged efficient structure.

The friction drive of the invention also provides the additionaladvantage of embodying a shaft I! which does not undergo axial movementin response to traversing of the roller. It is therefore unnecessary toassociate with the power delivery end of the device a universal joint orthe like providing axial lost-motion. In other words, the power may betaken directly from the left hand end of shaft l1 (Figs. 1 and 2) by asimple coupling or the like such as indicated in Fig. l as comprising ashaft 9! having a sleeve 92 secured thereto by a pin 93, and having setscrews 94 engaging the keyway of shaft 11.

The device is normally used in the position illustrated in Figs. 2, 3and 4, with spring 2! located at the bottom, and in order to provideadequate lubrication of the disc assembly at all times, the structurenow to be described is utilized.

The frame structure is below the disc axis is provided with a forwardlyextending flange 95, to which a chordally-shaped plate 91 is secured byscrews 98, A shim-like gasket 98 is clamped between the parts to providea liquid-tight joint. It is therefore apparent that plate 91 and flange96 form a reservoir which may be partially filled with lubricant. Theperiphery of disc 2! and bearings dipping into the lubricant serve tolift it upwardly in the structure where it may flow downwardly intobearing 23. Washer 3! prevents the lubricant around bearing 28 fromescaping from the mechanism.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiment is therefore to be considered in all respects as illustrativeand not restrictive, the scope of the invention being indicated by theappended claims rather than by the foregoing description, and allchanges which come within the meaning'arid range or equivalency of theclaims are therefore intended to be embraced thereby.

What. is claimed is:

1. In a, drive mechanism, a drive disc mounted for rotation; a shaftdisposed in spaced sub: stantially parallel relationship to the face ofsaid disc and" journalled for free rotation; a drive roller mounted foraxial sliding movement on said shaft, and having means driving-1ycoupling it thereto in all its shifted positions; means for yield.-ing-ly' urging said roller and disc into frictional driving engagement;a rotatable device, operable to apply solely coaxially directed forcesupon said. drive roller, for shifting the latter along said shaft, tothereby vary the speed ratio. between said disc and roller; and springmeans constantly acts.

ing uponsaid roller and tending to urge it endwise against the action ofsaid rotatable device, said spring means and said rotatable device actingdirectly along the axis of said shaft in such manner as to positivelypreclude any tendency to misalignsaidroller with respect to said shaft.

2. In a drive mechanism, a support, a disc. mounted for rotation on saidsupport; a shaft disposed in spaced substantially parallel relationshipto said disc; a roller having a hub; means mounting said roller foraxial sliding movement on said shaft, in frictional driving engagementwith said disc; means for urging said roller and disc into engagementunder a predetermined pressure, said roller mounting means comprising asupport structure having an arm disposed either side of said roller; abearing interposed between each of said arms and the hub of said roller;spring means connected to said support structure and urging the latteralong said shaft in one direction; a rotatable device for moving saidsupport structure along said shaft against the action of said springmeans, said spring means and said rotatable device coacting with eachother and said shaft in such manner as to positively preclude setting upany tendency to misalign said roller or said support structure withrespect to said shaft.

3. In a frictional drive, a support; a friction disc mounted forrotation about a fixed axis on said support; a shaft disposed in spacedparallel relationship to said disc; a roller having an elongated hub;means mounting said roller for axial sliding movement on said shaft, infrictional engagement with said disc; means for urging said roller anddisc into frictional driving engagement under a predetermined pressure,said roller mounting means comprising means for causing said roller hubto rotate in synchronism with said shaft and yet permitting free axialsliding movement therealong; a carriage; and bearing means supportingsaid hub upon said carriage; means for resiliently urging said carriagealong said shaft in one direction, comprising at least two springsreacting against said support and acting upon said carriage atdiametrically opposite points disposed equal distances from the axis ofsaid shaft; and means for moving said carriage and roller along saidshaft against the action of said springs.

4. The frictional drive defined in claim 3, wherein said last-namedmeans comprises an axially projecting sleeve provided on said carriageand cooperating with a second sleeve which is mounted for rotation onsaid support and restrained against endwise movement with respectthereto, one of said sleeves fitting within the other, and means forcausing said first sleeve and said carriage to be moved against theaction 7 of said springs when said second sleeve'is rotated.

5. The frictional drive defined in claim 3, together with guide means onsaid support parallel ing said shaft for supporting and guiding saidcarriage throughout its range of movement.

6. The frictional drive defined in claim 3, wherein said carriagecomprises an arm disposed either side of said roller and joined togetherexteriorly of the periphery of said roller, and said bearing meanscomprises an anti-friction bearing located in each of said arms andmounted on projecting end portions of said roller hub either side ofsaid roller.

7. In a frictional drive, a base, a disc mounted for rotation on saidbase; a pair of standards rising from said base adjacent said disc; ashaft journalled in one of said standards and a sleeve journalled in theother standard, said shaft projecting into said sleeve and havingbearing means for journalling it therein, whereby both said shaft andsaid sleeve are supported for independent rotation and are restrainedagainst endwise movement; a second sleeve concentric with and threadedlyengaging said first sleeve, and

adapted to undergo travelling movement along sleeve, to thereby traversesaid roller across theface of said disc and vary the speed ratio atwill.

HEINRICH HERMANNY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 578,536 Auriol Mar. 9, 1897693,290 Lucas Feb. 11, 1902 859,066 Hummel July 2, 1907 2,149,409 VanNorman et al. Mar. 7, 1939 2,357,035 Treese et a1 Aug. 29, 1944

